1. Field of the Invention
The present general inventive concept relates generally to equipment to aim radiant energy projected from a source to render objects visible, and more particularly, to a method and apparatus for aiming headlights of a vehicle.
2. Description of the Related Art
Properly aimed vehicle headlights provide visibility for a driver of a vehicle during times of limited visibility (e.g., at nighttime or in fog), and alert oncoming drivers to the presence of the vehicle. Improperly aimed headlights could unsatisfactorily render objects visible for the driver and blind or otherwise impair the sight of the oncoming drivers.
Headlights are adjustable in both vertical and horizontal directions by, for example, manipulating headlight aiming screws or other vehicle-mounted adjustable members. Adjustment of the headlight causes light projected from the headlights to be aimed according to aiming standards that may vary from country to country. For instance, in the United States, headlights of vehicles are aligned in compliance with aiming standards set forth by the Society of Automotive Engineers (SAE). The SAE standards differ from the aiming standards set forth in Japan and Europe, which also differ from each other.
A vehicle's headlights are required to be aimed in a number of instances. Upon manufacture of the vehicle, it is necessary to aim the headlights. Often, the headlights are aimed according to the standards of the country in which the vehicle is manufactured. Thus, if the vehicle is manufactured in one country and then exported to another country with different aiming standards than the country of manufacture, it may be necessary to reconfigure the aim of the headlights so that they comply with the aiming standards of the import country. Additionally, during the life of the vehicle, one or both headlights may require replacement or become misaligned (e.g., as a result of a collision or wear and tear of the headlight aiming screws). In these situations, it is necessary to reconfigure the aim of the headlights to comply with the applicable aiming standards.
Conventional headlight aimers are subject to a number of limitations. Generally, conventional aimers do not offer a variety of aiming standards and are instead set to a single standard based on the country of expected distribution and use of the device. Further, conventional aimers are typically unable to adapt to use with different types of headlights that may have different shapes and/or sizes (e.g., standard, auxiliary, fog, rectangular, round, and aerodynamic VOL and VOR headlamps). Instead, conventional aimers are commonly set to a single, common headlight type or normalized. Because various headlight types project light differently because replacement headlights may project their beams differently than original equipment supplied with the vehicle or for other reasons, normalization of headlight types may result in an undesired discrepancy from the applicable aiming standard with some headlight types and cause these headlights to perform poorly.
To aim a headlight, it is generally desirable to identify a reference point on the vehicle to ensure the aiming device is aligned with the vehicle. Conventional devices are commonly aligned visually with the vehicle using an operator's best guess with any small variance dismissed by the operator. Such manual alignment typically results in at least a minor undesired discrepancy from the applicable aiming standard, which causes headlights to perform poorly. Additionally, it is difficult to reproduce aiming tests using conventional aiming devices. In testing aim of the vehicle's headlights, if the conventional device is not properly aligned with the vehicle, the test may indicate that the vehicle's headlights are improperly aimed when in fact they are properly aimed in view of the relevant aiming standard. Furthermore, conventional headlight aiming devices may be heavy or difficult to maneuver in a service bay, or may inadequately compensate for inclinations, decries, or defects in the supporting surface.